Cut off device for electrically operated machines



J. L. BRYSON May 31, 1960 CUT OFF DEVICE FOR ELECTRICALLY OPERATEDMACHINES Filed June 19, 1959 JNVENTOR. L. fii'ysazg t arzes ATTORNEYUnited States Patent CUT OFF DEVICE FOR ELECTRICALLY I OPERATED MACHINESJames L.'Bryson, Clifton, NJ., assignor to Bryson Manufactoring Co.,Inc., Clifton, N.J., a corporation of New This invention relates toelectrically operated machines such as sewing machines having threadadvanced, usually under tension, from a source of supply, such asspools, to needle and/or loop members for the sewing operation.

It has been necessary for operators of a bank of such machines tocontinually check the thread passing through the machines to observethread breakage so as to stop the machine involved. The presentinvention provides a practical, highly efiicient device which willautomatically cut off operation of the sewing machine upon the breakingof any of the threads used in the operation thereof, and will maintainthe machine inoperative until the thread is effectively repaired orreplaced.

Examples of practical devices embodying the invention are'describedbelow and in the accompanying drawings; the invention is not limitedthereto, but covers all other forms coming within the scope or purviewof the disclosure herein.

As shown in the drawings:

Fig. 1 is an exploded perspective view, partly fragmentary of parts of adevice embodying the invention,

Fig. 2 is a partly fragmentary side elevational view thereof, inassembled relation but without the covering member for the plate, and

Fig. 3 is a perspective view of the .device applied to a sewing machinein the normal operation of the latter while the threads thereof remainunbroken.

In the drawings (Fig. 3) an electrically operated sewing machine isdesignated at 10, said sewing machine having a source of supply formovement of one or more threads 11 (in the direction of the arrow 12 andunder tension) to the needle or looper of the machine. The device 15 ofthis invention is interposed between the source of supply and the pointof stitching and comprises a bracket member 16 and plate 17 havingapertures 18, 19, respectively (Fig. 1) through which a pin 37 passes(Fig. 3) so that said bracket and plate members may be rotated to thuspredetermine the path of the thread through the apertures 20 in thespaced arms 21 which extend in parallel spaced relation from the bracketand through the intermediate thread loop members 22. By rotating thebracket '16 relative to the intermediate loop members 22, the drag ortension exerted on the thread may be readily adjusted to specific ordesired conditions. The invention permits the electric circuit to remainclosed while the threads 12 remain unbroken. However, when any one ormore of the threads break, the device immediately opens the electriccircuit. This end may be achieved by placing the parts -17, 23 in serieswith the power circuit for the machine or through use of switch,solenoid or other electrical energizing means whose circuit iscontrolled by the parts 17, 23.

The conductor 24 is (Fig. 2) mounted on an insulator 25 on plate 17, thelatter being electrically connected with the Wire 23 only when a threadbreaks, permitting the finger 26 to which the loop 22 for the brokenthread 2,938,972 Patented May 31, 1960 in question is secured, to .drop(Fig. 2 position) into contact with conductor. 24. The fingers 26 arepivotally mounted, at one end, on the stub shaft 27 which is fixed atone end to plate17 and extends therefrom. Conductor member 24 ispreferably mounted on plate 17 in spaced parallel relation to the stubshaft 27 and at a lower point on the plate than said shaft so that thefree ends 28 of the. fingers .26 will tend to rotate by gravity onto theconductor 24. The latter may be provided with contacts 29 (Figs. 1 and2) and the fingers 26 may have complementary contacts 30 (Fig. 2) tosave wear and tear. A cover 31 may be provided for the device (Fig. 3).The aperture 18 of bracket member 16 may be vertically elongated so asto permit the member 16 to be not only rotated on pin 37 but alsovertically shifted thereon relative to the plate 17 to further adapt thedevice to various conditions of use. Pin 37 may be directly mounted onthe sewing machine 'or, as shown in the drawings, passed through theaperture 32 at one end of a rod 33 which may be pivotally and fixedlymounted at the other end 34 by bolt 35 (Fig. 3) threaded to the machine10. The pin 37 (Figs. 2 and 3) may be a bolt, which may be tightenedwith a nut 36 after relative adjustment of the parts to the desiredposition, to hold them in that position.

Having thus described my invention, what I claim as new and desire tosecure by Letters Patent is:

l. A cut off device for connection with the electric circuit foroperation of a sewing machine, said device adapted to be positionedbetween the source of supply of thread for said machine and the needleto wln'ch said thread is supplied, said device comprising a bracket armsextending from said bracket, means to secure said bracket to said sewingmachine, a plate means to secure said plate to said machine, a stubshaft fixed, at one end, to the plate and extending therefrom parallelto said arms, a conductor member secured to said plate in spacedrelation to the stub shaft, a contact finger pivotally secured at oneend to the stub shaft and normally rotating thereon into contact, at theother end, with said conductor member, a thread loop member secured tosaid finger and extending upwardly therefrom, thread receiving aperturesprovided in said bracket arms, so that a thread of said machine may bepassed through one bracket arm through the loop member of the finger andthrough the other bracket arm, to normally hold said finger out ofcontact with said conductor member, said par-ts being so juxtaposed thatand, on breaking of said thread, the finger will rotate into contactwith said conductor member, so that said conductor member and said platemay be electrically connected to the operating circuit for the sewingmachine and, on movement of said contact finger into contact with theconductor member, the said electric circuit will be interrupted untilthe broken thread is replaced or repaired so that the finger may belifted by the replaced thread out of engagement with the conductormember.

2. In an automatic cut 01f device as set forth in claim 1, a contactstud on said conductor member to be so engaged by the finger when thelatter pivotally moves to a position for engagement with said conductormemher.

3. In an automatic cut off device as set forth in claim 1, means forrotatably securing said bracket to said sewing machine.

4. In an automatic cut olf device as set forth in claim 1, said meansfor securing the plate and bracket members to the sewing machinecomprising a rod secured to said sewing machine, said bracket and platebeing provided with apertures, and a pin passing through said aperturesand secured to said rod to thereby independently rotatably adjustablysecure said bracket to said rod.

5. In an automatic cut oli device as set forth in claim 4, said apertureso provided in said bracket member being vertically elongated to enablethe bracket member to be vertically adjusted relative to the plate.

6. In an automatic cut off device as set forth in claim 1, said meansfor securing the plate to the sewing machine comprising means forpivotally securing said rod at one end to said machine at apredetermined point, an aperture provided at the other end of said rod,said bracket and arms being provided with apertures and a ReferencesCited in the file of this patent UNITED STATES PATENTS Beachen July 16,1929 Vossen June 26. 1956 uni-y.-

